While heatwaves are a well-studied occupational hazard, the millions of workplace accidents that occur globally each year have a surprisingly neglected environmental contributor: air pollution.
Benjamin Hattemer and Ismael Moreno Martinez, who are final-year doctoral researchers at the EUI Department of Economics, collaborated on a project that analysed the connection between air pollution and accidents at work. Their joint research led to their co-authored working paper ‘Dust to Dust: Tracing Air Pollution’s Impact on Work Accidents’ which has recently been accepted by the Journal of the Association of Environmental and Resource Economists. We spoke with the two EUI economists and friends about their research, its main findings, and implications for policymaking.
Your research focuses on a specific source of natural air pollution: dust precipitation. Could you explain what dust precipitation is and describe its effects to broad geographical regions, especially Europe?
Dust precipitation occurs when strong winds lift fine particles from arid desert regions high into the atmosphere, where wind currents can carry them across vast distances, sometimes even between continents. Eventually, these particles fall again to ground level, deteriorating the air quality in the areas they land on. This is a natural phenomenon that happens worldwide and originates from major desert regions like the Sahara in North Africa, the Gobi Desert in East Asia, and deserts in the American Southwest.
The Sahara Desert is the main origin of the dust coming to Europe. People may be familiar with this phenomenon from the experience of finding their cars covered in a fine layer of dust. Many may have noticed the dust falling directly or seen it in the news during some of the very intense episodes that have occurred in the last few years (e.g. the episode last year in Athens, or the one in March 2022, visible in Switzerland).
The impact of these dust events extends well beyond dirty cars or a foggy view. When dust particles precipitate, they significantly increase the concentration of ‘particulate matter’ in the air. These tiny particles can enter our lungs and bloodstream. Moreover, this type of pollution can also penetrate indoors, especially in workplaces with limited ventilation. The Mediterranean Basin, the Caribbean, and parts of East Asia regularly experience these phenomena. With climate change intensifying desertification and altering weather patterns, dust events could become more frequent and severe in many regions, making it crucial to understand their full range of impacts on society, including workplace safety.
Dust precipitation is not always visible, and it is far more frequent than most people realise. In the Spanish municipalities we studied, for example, dust precipitation is present on approximately one in every five days, particularly during summer months.
Our study focused on Spain between 2010 and 2019, which offered ideal conditions for investigating this topic. Spain has a robust system for measuring and tracking dust events. As part of EU air quality compliance, the government routinely monitors when Saharan dust increases local pollution levels using specialised rural monitoring stations across the country. We matched this dust precipitation data with detailed administrative records on every work accident reported in Spanish municipalities with more than 50,000 inhabitants, covering roughly half the country's workforce.
Our analysis essentially asked: Did workplace accidents increase on days when dust precipitation occurred compared to similar days without dust?
Your paper links an increase in climate-induced dust movement to an increase in the work accidents. What motivated you to choose this research topic?
Workplace accidents affect millions of workers worldwide each year, imposing substantial costs on individuals, businesses, and healthcare systems. The World Health Organization estimates that 1,000 workers die on average each day due to occupational accidents worldwide. The burden is severe even in high-income countries with strict occupational safety regulations. In the EU, at least 2.8 million workers registered non-fatal accidents, and 3,298 died on the job in 2023. In Spain alone, our data reveals that more than 4 million work accidents took place between 2010 and 2019.
Policymakers and the public are increasingly aware of how heatwaves and high temperatures affect worker safety. However, there is another, less explored, environmental factor that can compromise the safety of workers: air pollution. In our research, we focused on a particular source of air pollution - dust precipitation - for two main reasons. First, dust precipitation is a source of natural air pollution sensitive to climate change and its effects on desertification patterns and rising temperatures. Second, dust events act like natural experiments because they occur for reasons unrelated to local economic conditions. This makes the study of its causal effects on work accidents relatively easy, which is harder to do with the air pollution generated from cars or factories.
Previous research had primarily examined how dust affects health outcomes like respiratory diseases or mortality, particularly in regions close to deserts. However, dust also has more subtle effects on healthy workers. Breathing air pollution can cause fatigue, reduced concentration, irritability, and slower reaction times; we hypothesised these symptoms could increase human error at work, leading to more accidents. Given that dust storms are becoming more common and affect vast populations, even far away from desert regions, understanding their workplace safety implications seemed both timely and important for developing appropriate policy responses.
Could you explain the link you found between dust precipitation events and the incidence of workplace accidents?
Our research reveals that dust precipitation significantly increases workplace accidents. A day of dust precipitation raises work accidents by 1.4% compared to dust-free days. While this percentage might seem modest, it translates into a substantial burden: Approximately one in every 400 work accidents in Spain can be attributed to dust pollution. To put this in perspective, the overall impact of dust on workplace safety is about one-fifth as large as the impact of high temperatures, a well-recognised occupational hazard.
What makes these findings particularly striking is how widespread the effects are. Dust precipitation increases accidents across nearly all worker categories, affecting both men and women, workers of different ages, those in various occupations (from construction to office work), and employees across the wage distribution. This pattern strongly supports our hypothesis that dust exposure impairs physical and cognitive performance in ways that increase human error across diverse work contexts. Our hypothesis is that exposure to air pollution might lead to miscalculations or delayed responses to hazards, which increases accident risk for a wide range of workers.
For instance, on a day of dust precipitation, a machine operator adjusting settings on a high-speed assembly line may experience a momentary lapse in concentration, leading to entanglement or crushing injuries from moving parts. Similarly, a warehouse worker stocking shelves may misjudge a box’s weight and sustain a lifting-related back injury, or a waitress navigating a crowded restaurant could slip and fall if she overlooks a spilled glass on the floor. In any workplace, from factories to cafés, poor air quality impairs concentration and thus increases injury risk.
However, we found an important exception: Workers in the ‘top wage quintile’ - meaning those with the highest income - showed no significant increase in accidents during dust events. This suggests that higher-earning workers, who typically have more job flexibility and bargaining power, may be better able to protect themselves. They might adjust their work hours, take a day off from work, or postpone risky tasks when air quality deteriorates.
Importantly, dust affects not only minor incidents but also severe accidents. Our research highlights significant increases across all severity levels, including accidents requiring more than two months of sick leave. Moreover, workers in the riskiest occupations – such as those in the construction and manufacturing sectors - experience 22 times more additional accidents per capita during dust events than workers in safer-than-average jobs, highlighting important equity dimensions of environmental workplace risks.
Drawing upon your research findings, what specific and actionable recommendations would you propose for policymakers and occupational safety bodies to enhance workplace safety?
Our findings point to several concrete policy directions focused on adaptation, updated regulations, and targeted protection for high-risk workers.
First, because dust precipitation is largely a natural phenomenon that cannot be prevented, adaptation strategies should take priority. We recommend developing enhanced monitoring and warning systems that could alert workers and employers when dust events are occurring, similar to existing heat warning systems. These alerts could trigger protective protocols in high-risk workplaces, such as postponing particularly hazardous tasks, implementing additional safety checks, or adjusting work schedules.
Second, occupational health and safety regulations should be expanded to explicitly recognise air pollution from natural sources as a workplace risk factor. Currently, health and safety regulations in most countries focus primarily on protecting workers from long-term exposure to pollution generated inside the workplace. Our research demonstrates that acute episodes of external air pollution can also create significant hazards. This is crucial because fine dust particles can penetrate indoor environments, meaning that workers are likely exposed to dust pollution both outside and during work hours, especially in workplaces with limited ventilation or filtration systems.
Third, policies should prioritise protecting workers in high-risk occupations, such as construction, manufacturing, or other physically demanding jobs where accident rates are already high. These workers experience disproportionately large increases in accidents per capita during dust events. Enhanced protections could include requirements for employers to improve air filtration in enclosed workspaces, the provision of appropriate respiratory protection equipment during dust events, or temporarily modifying work practices when air quality deteriorates.
Additionally, while abating dust at its source is impossible, other policies could target human-made emissions during dust events. Since dust episodes can trap other pollutants near ground level, temporarily reducing emissions from industrial sources or traffic during dust events could help minimise the combined effects of multiple pollutants on workers’ health and safety.
Finally, our research has implications for how we interpret and respond to temperature-related workplace risks. Many existing interventions focus solely on heat stress as the mechanism linking high temperatures to workplace accidents. However, in places where high temperatures often coincide with dust precipitation, the estimated impacts of heat may partially reflect the air pollution effects. Policymakers should therefore consider both heat and dust hazards when designing safety interventions.
Benjamin Hattemer is a doctoral researcher at the EUI Department of Economics. Benjamin’s PhD thesis entitled “Essays on Environmental and Labor Economics: Physical Risks and Policies” is supervised by former EUI Professors Thomas Crossley (supervisor) and Alexander Monge-Naranjo (co-supervisor).
Ismael Moreno Martinez is a doctoral researcher at the EUI Department of Economics. Ismael’s doctoral research is supervised by former EUI Professor Thomas Crossley (supervisor) and EUI Professor Andrea Ichino (co-supervisor).
Read the paper ‘Dust to Dust: Tracing Air Pollution’s Impact on Work Accidents’ on SSRN.
Photo by Nils Schirmer on unsplash.com.